Photographic apparatus



June l2, 1951 w. w. WARD A 2,556,784

. PHOTOGRAPHIC APPARATUS Filed March 25, 1950 l 2V Sheets-Sheet 1 INVENTOR.

45 WALLACE nl WARD f Arme/Vey W. .W. WARD PHOTOGRAPHIC APPARATUS June l2, 1951 '2 Sheets-Sheet 2 Filed March 25, 1950 R@ y mw. M mw. ma n A A L m W Patented June 12, 1951 UNITED STATES PATENT OFFICE PHOTOGRAPHIC APPARATUS Wallace W. Ward, Bloomfield, N. J., assignor to Products Engineering Laboratories Co., Inc., Newark, N. J., a corporation of New Jersey Application March 25, 1950, Serial No. 151,951

(iCl. 88-23) e 4 Claims. l

This invention relates to photography apparatuszand, more particularly, to a novel combined range finder or distance meter, photometer or exposure meter, and flash calculator.

At present, measurement of distance, measurement of light values, and calculations of flash brightness are effected by individual instruments. Distance measurements, for example, are effected by range finders or distance meters of the military, split field, or coincidence types. Light values are separately measured by an exposure meter which may, for example, be of the electric type orfof the light extinction type. Flash calculators are usually of the straight or circular slide rule variety. A photographer interested in obtaining the best results thus has to carry and independently manipulate three diiferent instruments..` Nevertheless, accurate subject distance, lighting, and flash measurements are essential if the best pictures are to be obtained.

Thepresent invention is directed to a single instrument, which may be termed the unit, by means; of which all three measurements can be madein a coordinated and properly interrelated manner. To this end, the unit comprises a twosection casing forming a housing, the sections having, at one end, aligned rectangular openings, and one opening carrying a pane of transparent rigid material, the sections being united by an eyelet and having congruent arc shaped openings centered on this eyelet. The front or face section has a segment shaped portion offset from the remainder of the front face of the section. This portion has the arced aperture formed therein and also carries the front end of the eyelet.

The eyelet acts as an axis for a plurality of interacting, indicia carrying dials. The outern most dial, which is preferably colored and sector shaped, carries film speed indicia at predetermined angular spacings, for example 9, and these indicia are observable through a radial aperture in the offset portion. The second dial is likewise sector shaped and carries light value indicia. The third dial carries two sets of shutter speed indicia, and is circular. These three dials are frictionally biased against the overlying sector portion of the forward casing section.

Also rotatably mounted on the eyelet is a fourth dial, which is circular and carries F-stop indicia. On its rear surface this dial carries a projecting pin which cooperates with a cam surface on a slide plate secured between the casing sections. This vSlide. plate fits within the marginal edges of the casing sections and is held in place for 2 vertical reciprocation by the central eyelet passing through the vertical slot thereof, and an eared guide member carried on said eyelet. A series of uniformly spaced apertures are arranged on an f arc in the guide member, said apertures being aligned with the arc apertures in the casing sections. Behind the apertures of the guide member is a photographic step wedge of semi-transparent material, each step being aligned with a guide aperture. The arc aperture in the rear casing section is covered by a light diffusing screen of translucent material.

The fourth dial is rotated by the slide reciprocable, as aforesaid, along the casing into and out of registration with the rectangular apertures. This slide has a plurality of apertures arranged on a diagonal line and each longitudinally aligned with those of the guide member. The slide acts as a range finder, in a manner to be described, and its apertures cooperate with the guide member apertures to measure light values. A spring biases the fourth dial in one direction, and the slide, engaging the pin, acts to rotate the fourth dial as the slide is moved longitudinally. Thus, as successive light values are measured by the photographic wedge apertures, the fourth dial is correspondingly rotated to align F-stop indicia with related indicia on the rst three dials.

In its range finding function, the slide is cooperable with distance markings on the pane in the rectangular aperture of the front casing section. To provide the necessary base line correlation with such distance markings, a neck cord of predetermined length is secured to the unit.

With the foregoing in mind, it is an object of the present invention to provide a combined photometer, range finder, and a distance coupled flash calculator unit.

Another object is to provide such a unit including cooperating dials, slide and light measuring means having correlated interrelated movement.

These, and other objects, advantages and novel features of the invention will be apparent from the following description and the accompanying drawings. In the drawings:

Fig. 1 is a front elevation view of the unit;

Fig. 2 is a rear elevation View of the unit;

Fig. 3 is a median sectional View of the unit;

Fig. 4 is an exploded isometric View of the unit;

Figs. 5 and 6 are elevation views of the F-stop dial, guide member and slide, showing two different relative positions thereof; and

Fig. 7 is a diagrammatic illustration of the geometrical relations upon which the range finder is based.

Referring to Figs. 1 through 4, the combination unit includes a casing comprising front casing section I I and rear casing section I2 having marginal edges' or flangesl I3 and I4. The casing sections are formed With aligned, congruent rectangular apertures or windows I6 and I'I, which are bounded by inturned flanges I8 and I9. Aper ture I6'is closed by a pane 20 of translucent material having distance indicia 2| thereon, for example feet and meters The two casing sections are joined by an clon* gated eyelet 22, which is the center of a pair of aligned, congruent, arc apertures 23 and 24 in the two sections, each extending approximately 72. Aperture 23 is formed in an offset, sector shaped portion 25 which has a radial slot 26. The latter is cooperable with film speed indicia 3|, such as A, 13, C and D on a sector shaped dial 30. Indicia 3| are spaced approximately 9 apart and at progressively decreasing distance from eyelet 22. Dial 3D is preferably colored, and has an operating tab 32.

These indicia are used in cooperation with a table 33 on the surface of section I4, which table relates flash bulb sizes and filter numbers to indicia 3|. For example, a 16x filter is related to index A. The manner of using these indicia will be described more fully hereinafter.

A second sector shaped dial 4B underlies dial 30, and carries light value indicia 4| such as dull, hazy, average bright, brilliantj and flash The first four indicia, for example, are spaced approximately 9 apart, whereas flash is spaced approximately 18 from brilliant. Dial 4|), whose use will likewise be explained hereinafter, has an operating tab 42.

A shutter speed dial 50, which is circular, underlies dial 40. This dial carries a first set of indicia 5| spaced approximately 9 apart and ranging from l/goo to 1/2 followed by 1, 2, 4, 8, and 15. A second set of indicia 52 follows and overlaps the iirst set, this second comprising 800, 400, 200, 100, 50, 20, 12, f6, 3, 1.6 and .8. The iii-st five indicia 52 overlap and are radially aligned with the last five indicia 5 I. The function and operation of dial 5D will be described hereinafter.

The three dials 30, and 50 are secured, in frictional contact with each other, to section EI by an eyelet 2l surrounding eyelet 22.

A fourth dial having F-stop indicia 8| spaced approximately 9 apart underlies dial 50 and is rotatable on eyelet 22. These indicia range from 1.4 through 45. A drive pin G2 is secured eccentrically to the back surface of dial 60 and engages a cam surface 55 formed on the slide 45. The latter has a vertical slot 44 through which eyelet 22 passes and a series of apertures 45 arranged along a diagonal line. A guidel plate 55, the edges of which engage the sidewalls of the casing and through the base of which eyelet 22 passes for iixedly maintaining the same in relation to the casing, is provided with bent ears d0 which serve as bearing surfaces for the sides of the slide 45, which may be vertically reciprccated within the casing in the amount dened by the length of the slot 44. Guide plate has a plurality of apertures 5l equal in number to the apertures 40 of slide said apertures being arranged in an arc centered on eyelet 22 and each aperture being laterally aligned with an aperture 455 of the slide 4,5. A stepped photographic wedge 4l' of semi-transparent material is secured to the back of the 4 guide plate 55 with each step underlying an aperture 51 thereof.

A spring 58 iits over eyelet 22 and has one end anchored against guide member 55 andthe other end anchored against pin 62. This pin biases dial 50 in a counter-clockwise direction, and dial 60 is moved in a clockwise direction by slide 45. As will be explained, this coordinates the reading of dial 60 with the light values measured by step wedge 41. A diffusing screen 49, of nat translucent material, is mounted over arc aperture 24 behind apertures 46. An adjustable neck cord S5 is xed to the lower end of slide 45, as by being tied to an eyelet 59.

It will be noted that the indicia on dials 30, 4G, 5|) and 60 are equally angular spaced. In the case of the indicia of dial 50, each index 5| or 52 is progressively 1/2 or twice the value of an adjacent index, as is also true of the indicia 6| of dial 60. Similarly, the indicia 4| of dial 40 indicate qualitatively light values progressively IAE or twice that of adjacent indicia. lThe same is true of the indicia 3| of dial 30, which denote liash bulbs each having twice the light value of the next smaller size bulb, or filters having the same progressive relation as to value. Having these in mind, the operation of the unit will be apparent from the following description.

In using the unit as a range finder or distance meter, the slide 45 is used in cooperation with pane 20. For this purpose, neck cord is adjusted to provide, when taut, a xed distance, such as 131/3" from the eye to pane 20. The head or face height of a subject is assumed to be, for example, 7%, within the limits of practical accuracy desired. Referring to Fig. '7, the distance may then be determined by the principle of similar triangles. If the line of sight passes through pane 20, one limit line will be the upper edge of aperture I6. In sighting on a person, for example, slide 45 is moved down until the line of sight over the top edge of the slide hits the chin ofV the subject when the line of sight under the upper edge of aperture i6 hits the top of the subjects head. The indicia 2| in line with the upper edge of slide 45 thengives the distance in feet or meters.

The angle formed between the limit sight lines varies with the distance of the subject. Knowing the base of the observed triangle to be '2Q/4^ and the altitude of the triangle based on pane iii to be 131/5, the indicia 2| can be calibrated to indicate the altitudes of other similar or proportional triangles having different vertex angles. These altitudes are the distance of the subject from the eye. With a little practice, the distance of other objects can also be determined..`

In using the unit as an exposure meter, dial 30 is rotated until the proper filter index 3| appears in slot 26. The index edge 34 of dial 30 then has a certain angular position. Dial 5D is then rotated until a selected iilm speed indicia 5i is registered against edge 34.- The indicia 52 are then in a certain angular relation to dial 50,;

The index edge 42 of light value dial di) is then set against the desired shutter speed indicia 52 of dial 50.

Slide 55 isl then moved downwardly, successively registering apertures 51 with successive apertures 45. This is continued, with lighted dots appearing in successive apertures 46, until the light no longer penetrates. Slide E5 is then moved upwardly until the lighted dot reappears. During this slide movement, dial B-is rotated by the earn and spring action *on pin 62. The proper 5 F-stop value may then be read from dial 60 opposite the indicia 4i most closely descriptive of the general lighting conditions.

To use the unit as a ash calculator, the proper letter' designation f or the iash bulb is taken from table 33 and set in slot 2S by moving dial 35i. The nlm speed dial 5i) is then set, as described, and dial ill moved until its index edge i12 registers at vthe desired lin speed indici@u 52. The range finding procedure is then followed, moving slide 55 and thus dial 68. "Ihe proper F-stop can then be taken from dial Si? at the flash indication oi dial 40.

While a specic embodiment of the invention has been shown and described in detail to illustrate the application of the principles thereto, it should be understood that the invention may be otherwise embodied Without departing from such principles.

What is claimed is:

l. Photographic apparatus comprising, in combination, a casing having spaced aligned openings therein, a step wedge aligned lwith the openings, a slide movably mounted in said casing and having apertures each alignable `with an opening at a predetermined position of said slide, a dial movably mounted on said casing and carrying F-stop indicia, index means associated with said dial, means interconnecting said slide and said dial to move the latter during movement of said slide, whereby the proper F-stop may be determined from the relative positions of said dial and index means,' a sighting aperture arranged to be controlled by said slide, and having an edge, distance indicia associated with the sighting aperture and arranged along the direction of movement of said slide, and means operable to position said apparatus at a iixed distance from the users eye, whereby said distance indicia, in cooperation with the end of said slide, will indicate the distance of a subject of known dimensions viewed between said edge and the slide end.

Photographic apparatus comprising, in combination, a casing having spa-ced aligned openings therein, a step wedge aligned with the openings, a slide movably mounted in Said casing and having apertures each alignable with an opening at a predetermined position of said slide, a rst sector shaped dial rotatably mounted on said casing and carrying nlm speed indicia and having an index edge, a second sector shaped dial rotatably mounted on said casing and carrying brightness indicia, a first circular dial rotatably mounted on said casing and carrying shutter speed indicia cooper-able with said index edge, said second sector shaped dial having an index section alignable with a selected shutter speed index, a second circular dial rotatably mounted on said casing and carrying F-stop indicia cooperable with said brightness indicia, all of said dials be`I ing concentric, means interconnecting said slide and said second dial to move the latter during movement of said slide, whereby the proper F- stop may ne determined from the relative positions of said second dials, a sighting aperture arranged to be controlled by said slide, and having an edge, distance indicia associated with the sighting aperture and arranged along the direction of movement of said slide, and means operable to position said apparatus at a xed distance from the users eye, whereby said distance indicia, in cooperation with the end of said slide, will indicate the distance of a subject of known dimensions viewed between said edge and the slide end.

Photographic apparatus as claimed in claim 2, in which the indicia of any dial have a 2:1 ratio of indicia `value between successive indicia.

4. Photographic apparatus as claimed in claim 2, in which the indicia of any dial have a 2:1 ratio of indicia value between successive indicia and are arranged at equal angular distances from each other.

WALLACE W. WARD.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,001,840 Gauthier et al. May 21, 1935 2,205,312 Schwartzmann June 18, 1940 FOREIGN PATENTS Number Country Date 405,881 Great Britain Feb. 15, 1934 

